State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Lu , Shanghai 200032 , China.
School of Physical Science and Technology , ShanghaiTech University , 100 Haike Road , Shanghai 201210 , China.
J Am Chem Soc. 2019 Feb 13;141(6):2636-2644. doi: 10.1021/jacs.8b12965. Epub 2019 Jan 31.
An intramolecular dearomatization of indole derivatives based on visible-light-promoted [2+2] cycloaddition was achieved via energy transfer mechanism. The highly strained cyclobutane-fused angular tetracyclic spiroindolines, which were typically unattainable under thermal conditions, could be directly accessed in high yields (up to 99%) with excellent diastereoselectivity (>20:1 dr) under mild conditions. The method was also compatible with diverse functional groups and amenable to flexible transformations. In addition, DFT calculations provided guidance on the rational design of substrates and deep understanding of the reaction pathways. This process constituted a rare example of indole functionalization by exploiting visible-light-induced reactivity at the excited states.
基于能量转移机制，实现了吲哚衍生物的分子内去芳构化，通过可见光促进[2+2]环加成反应。在温和条件下，以高收率（高达 99%）和优异的非对映选择性（>20:1 dr），可直接获得通常在热条件下难以获得的高度应变的环丁烷稠合角四环螺吲哚啉。该方法还与各种官能团兼容，并适合灵活转化。此外，DFT 计算为底物的合理设计和对反应途径的深入理解提供了指导。该过程构成了利用激发态下可见光诱导的反应性对吲哚进行功能化的罕见实例。
